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Downriver AM transmitters

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k8jd
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Location: Commerce, MI

Re: Downriver AM transmitters

Post by k8jd » Sun Nov 08, 2020 9:43 pm

CK-722 wrote:
Sun Nov 08, 2020 1:05 am
The old Night WXYT pattern on 10 Mile Rd. used 165 degree towers, and went as well to the South as to the North.

The Nondirectional Day pattern was the equivalent of 8250 watts referenced the the legacy Class B efficiency minimum of 282 mV/m @ 1 kW @ 1 km.

[img]https://www.fccinfo.com/image.php?S

This is the pattern with the two tower Southfield array, when I worked there!
I recall running field strength readings at a few monitoring points in the middle of the night !
I recall the chief telling me they were trying to get a pattern that was usually done with three towers but ABC was too cheap to put up a third tower
:lol:
Now I can barely hear WXYT , at night, out here with 50 kW and the deep null to the northwest !



CK-722
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Re: Downriver AM transmitters

Post by CK-722 » Mon Nov 09, 2020 2:20 am

Although the null to the West originally was to protect WHBF/WKBF in Rock Island, IL, WCMR Elkhart, IN and WWCA Gary, IN fit into the pattern so they got good protection. WHBF/WKBF was deleted this year. If the new pattern wasn't so complex, they might have been able to let that null out a little, and certainly the old pattern could have been easily modified.


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Rich F.
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Re: Downriver AM transmitters

Post by Rich F. » Mon Nov 09, 2020 3:56 am

k8jd wrote:
Sun Nov 08, 2020 9:43 pm
... Now I can barely hear WXYT , at night, out here with 50 kW and the deep null to the northwest !
Below is a plot showing about what to expect for the nighttime GW field of WXYT in/near Commerce Twsp, MI — something like 8 mV/m.

The slope of their licensed nighttime pattern is getting steep toward the West of that compass bearing, so their field could be a fair amount less than 8 mV/m there, at the exact physical location of the receive site.

It looks like they might be having a noticeable amount of interference there from their own nighttime skywave, too.

Image



k8jd
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Re: Downriver AM transmitters

Post by k8jd » Mon Nov 09, 2020 12:41 pm

Never actually measured it but now I had to !
WXYT transmitter to my house, distance 38.75 Miles, azimuth angle is 350.5 degrees.
Pretty close to the night time null in the pattern.
The distance may also be a factor for whatever angle the sky wave is going out.
40 years ago I lived 4 miles south of the old transmitter site, and heard the 3rd harmonic quite easily on the 80 M amateur band.



innate-in-you
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Re: Downriver AM transmitters

Post by innate-in-you » Sun Dec 27, 2020 12:53 am

CK-722 wrote:
Sun Nov 08, 2020 1:05 am
The old Night WXYT pattern on 10 Mile Rd. used 165 degree towers, and went as well to the South as to the North.

The Nondirectional Day pattern was the equivalent of 8250 watts referenced the the legacy Class B efficiency minimum of 282 mV/m @ 1 kW @ 1 km.

Image
Speaking of WXYT (AM), I wonder if they could add more territory, as the result of the deletion of WKBF in Rock Island, IL.

WKBF was the other "senior" station on the channel.

Of course, WXYT's unique array could cause problems protecting other stations - perhaps they could send much more RF to the west, even with the existing array - or does the strange positioning of the towers make it impossible to get the array to protect everyone?



CK-722
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Re: Downriver AM transmitters

Post by CK-722 » Sun Dec 27, 2020 1:09 am

I don't know exactly how this pattern was designed by Glen Clark's supercomputer. He himself described the software as using "fuzzy logic". I had recently gained a rapport with Glen when he passed away, and I wish I had had time to discuss this design. I doubt if you could do exactly what you wanted with it without moving at least some of the towers around.

WCMR and WWCA have fairly low NIFs, and without changes in the rules, I don't think you could increase the IDF greatly to the West. Some increase perhaps.

Rumors have it that MacDonald Garber would have sold WMKT to CBS/Entercom, but they didn't want to spend the money. WMKT had a CP for 50 kW nondirectional Days, which was extended with a new APP to six years, which would have destroyed WXYT during Critical Hours. The power bills were prohibitive, and they got two near 3 kW Class A equivalent translators, so it wasn't built.


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paul8539
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Re: Downriver AM transmitters

Post by paul8539 » Tue Jan 05, 2021 2:43 pm

Isn't 910 down there too? Didn't they move there after moving out of Flint?



innate-in-you
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Re: Downriver AM transmitters

Post by innate-in-you » Tue Jan 05, 2021 3:16 pm

paul8539 wrote:
Tue Jan 05, 2021 2:43 pm
Isn't 910 down there too? Didn't they move there after moving out of Flint?
It's in Carleton (an 8 tower array which is about half the size of Carleton itself).

It booms at my in-laws house, right in their crosshairs.

It actually has only a fair signal in the Eastern portions of the Detroit area.



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WOHO
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Re: Downriver AM transmitters

Post by WOHO » Wed Jan 06, 2021 8:37 am

I'm surprised that 910 doesn't have a better signal to the south, especially since they went thru the trouble of snuffing-out 900KHz out of Fremont, Ohio? Can't get an HD lock until north of Monroe!



fuzzpower
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Re: Downriver AM transmitters

Post by fuzzpower » Thu Jan 07, 2021 7:14 am

Co-channel WPFB in Middletown, OH (halfway between Dayton and Cincinnati) is likely the reason there’s not much to the south.



CK-722
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Re: Downriver AM transmitters

Post by CK-722 » Thu Jan 07, 2021 11:09 am

The reason that the WFDF signal is weaker on the Eastern part of the Metropolitan Area is that there is a null toward a VACANT allotment on 910 in Lindsay, Ontario that used to be occupied by CKLY. It likely will never be occupied now. The Reason WWJ is weaker on the FAR Eastern side of Michigan near the St. Clair River is that there is a VACANT allotment on 950 in Barrie, Ontario that used to be occupied by CKBB. It likely will never be occupied either. The other difference is that the WFDF transmitting site is several miles WEST of the WWJ site. Originally, Glen Clark wanted to put the new WFDF site next to the WJR site in Riverview, but the NIMBYs prevailed.


Is THAT where they got the idea for the 486-SX?

Same (x, y, z), different (t)

Your bullet missed my trial balloon.

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k8jd
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Re: Downriver AM transmitters

Post by k8jd » Thu Jan 07, 2021 12:07 pm

Since Canada is shutting down Many high power AM stations, switching to FM , you think they could relax the protection rules from the US AM statons.
I guess they expect the hunter/trappers who live in the far bush to toss out am radios and get satrellite radios. FM just does not usually go very far over the horizon !



k8jd
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Location: Commerce, MI

Re: Downriver AM transmitters

Post by k8jd » Thu Jan 07, 2021 12:11 pm

innate-in-you wrote:
Tue Jan 05, 2021 3:16 pm
paul8539 wrote:
Tue Jan 05, 2021 2:43 pm
Isn't 910 down there too? Didn't they move there after moving out of Flint?
It's in Carleton (an 8 tower array which is about half the size of Carleton itself).

It booms at my in-laws house, right in their crosshairs.

It actually has only a fair signal in the Eastern portions of the Detroit area.
For a whle I was spotting AM arrays on Google Earth and driving around tking photos of them. the WFDF array looks like two four tower rectangles, side by side, each aimed at a slightly different angle north !
I believe directional arrays were once figured out by an engineer with a slide rule and now they are computer designed with Gigantic programs.



CK-722
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Re: Downriver AM transmitters

Post by CK-722 » Thu Jan 07, 2021 12:34 pm

k8jd wrote:
Thu Jan 07, 2021 12:07 pm
Since Canada is shutting down Many high power AM stations, switching to FM , you think they could relax the protection rules from the US AM statons.
I guess they expect the hunter/trappers who live in the far bush to toss out am radios and get satrellite radios. FM just does not usually go very far over the horizon !
Maybe that's why CFRX continues to operate on 6070 kHz with just 1 kW. With all the interference on 1010 kHz, you'd think they would be able to increase the power up to 50 or 100 kW or so on 6070 kHz, also given the near abandonment of International shortwave.


Is THAT where they got the idea for the 486-SX?

Same (x, y, z), different (t)

Your bullet missed my trial balloon.

RTN Price. Not guaranteed. As of 12:30, 157.71 Down 0.22.

Artificial Intelligence is a Child that needs a Parent to guide it through.

CK-722
Posts: 1284
Joined: Sun Dec 16, 2018 3:53 pm

Re: Downriver AM transmitters

Post by CK-722 » Thu Jan 07, 2021 12:55 pm

k8jd wrote:
Thu Jan 07, 2021 12:11 pm
innate-in-you wrote:
Tue Jan 05, 2021 3:16 pm
paul8539 wrote:
Tue Jan 05, 2021 2:43 pm
Isn't 910 down there too? Didn't they move there after moving out of Flint?
It's in Carleton (an 8 tower array which is about half the size of Carleton itself).

It booms at my in-laws house, right in their crosshairs.

It actually has only a fair signal in the Eastern portions of the Detroit area.
For a whle I was spotting AM arrays on Google Earth and driving around tking photos of them. the WFDF array looks like two four tower rectangles, side by side, each aimed at a slightly different angle north !
I believe directional arrays were once figured out by an engineer with a slide rule and now they are computer designed with Gigantic programs.
I was just starting to get a good rapport of discussion with Glen Clark when he passed away.

You are correct that there are two "near" parallelograms in the array. It actually looks like only one tower is out of alignment for one parallelogram.

But is it two parallelograms next to each other, or two INTERLOCKING parallelograms, in terms of the design? That was something that I had always wanted to ask Glen.

Does anyone know what happened to his computer array/supercomputer and the software he used? I would assume that Ron Rackley was poised to inherit it, but he died right before Glen. Maybe duTriel and Lundin have it?

https://licensing.fcc.gov/cdbs/CDBS_Att ... &exhcnum=1


Is THAT where they got the idea for the 486-SX?

Same (x, y, z), different (t)

Your bullet missed my trial balloon.

RTN Price. Not guaranteed. As of 12:30, 157.71 Down 0.22.

Artificial Intelligence is a Child that needs a Parent to guide it through.

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